SOLUTION: How would you solve the following word problem by setting up two equations? The sum of the radii of two circles is 8 cm. Find the radii if the sum of the areas of the circles is

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: How would you solve the following word problem by setting up two equations? The sum of the radii of two circles is 8 cm. Find the radii if the sum of the areas of the circles is      Log On


   

Question 242858: How would you solve the following word problem by setting up two equations?
The sum of the radii of two circles is 8 cm. Find the radii if the sum of the areas of the circles is 32picm^2.
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
Let one of the radii=r and the other 8-r
pi*r^2+pi*(8-r)^2=32pi
pi*r^2+pi*(r^2-16r+64)=32pi
2pi*r^2-16pi*r+64pi-32pi=0
6.28r^2-50.27r+100.53=0
r=4
Both radii are 4cm
.
Ed